The present invention relates to an anti-human pulmonary carcinoma monoclonal antibody, which is capable of highly frequent reaction with three tissue types of human pulmonary carcinoma, i.e. squamous cell carcinoma, adenocarcinoma and large cell carcinoma, and is non-reactive with human small cell carcinoma and normal human lung cells. The antibody recognizes glycoproteins as the antigen and belongs to the class IgM.
Since the monoclonal antibody according to the present invention is capable of effectively detecting lung cancer except for small cell lung carcinoma, it is useful for the pathologic and serologic diagnosis of lung cancer.
Monoclonal antibodies which are capable of specifically reacting with various human cancers as constructed by the technique of obtained hybridomas have recently been reported. While there are many reports on monoclonal antibodies capable of reacting with human lung cancer [Cancer Res., 42, 150 (1982); Cancer Res., 42, 3187 (1982); J. Surgical Res., 30, 403 (1981); Transplantation Proceed , XIII (4), 1942 (1981); J. Immunol., 131 (1), 497 (1983); Abstracts of Papers, Japan Society of Immunology, P. 212 (Abstract No. 107) (1983); J. Immunol., 131 (1), 497 (1983); Cancer Res., 46, 4438 (1986); Cancer Res., 47, 1267 (1987)], no monoclonal antibodies being capable of equally reacting three tissue types of human lung cancer, i.e. squamous cell carcinoma, adenocarcinoma and large cell carcinoma but non-reactive with small cell carcinoma cells have been known.
Carcinoembrionic antigen (CEA), known as tumor marker, is present not only in all pulmonary carcinoma tissue types, but also in normal lung tissue and serum, and is so, not specific to lung cancer. Thus, the positive rate to lung cancer is not very high with CEA.
The remedy and prognosis of small cell lung carcinoma among four types of pulmonary carcinoma are quite different from those of the other three types. Accordingly, a monoclonal antibody which can distinguish squamous cell carcinoma, adenocarcinoma and large cell carcinoma from small cell carcinoma, if available, would be useful in the diagnosis of lung cancer.
The present inventors have found that monoclonal antibodies produced by hybridomas between spleen cells of a mouse immunized with membrane fractions of human squamous cell lung carcinoma and murine myeloma cells have good reactivity with not only squamous cell lung carcinoma to be used as the immunogen but also to lung adenocarcinoma and large cell lung carcinoma and so are applicable in pathologic, serologic and pleural effusional diagnosis.